The objective of this continuation proposal is to train outstanding young M.D.s, M.D./Ph.D.s and Ph.D.s for a successful career in investigative Nephrology. The rationale for submitting this application for the continuation of our training grant is our belief that Mount Sinai School of Medicine offers diverse scientific opportunities in an outstanding research environment, that we have a faculty that is dedicated to training physician-scientists for a career in academic Nephrology, and that we would like to contribute and have an impact on the education of future investigative Nephrologists. A diverse faculty has been integrated into the current application including faculty from the Mount Sinai School of Medicine's Institute for Gene Therapy and Molecular Medicine, the Center for Immunobiology, the Transplant Institute, the Cancer Center and the Departments of Human Genetics, Medicine (including Nephrology, Hematology/Oncology, Liver Diseases, and Infectious Diseases), Ophthalmology, Pediatrics (including Nephrology, Liver Diseases and Infectious Diseases), Pharmacology & Biological Chemistry, and Physiology & Biophysics. In addition, two outstanding physician scientists, one previously at Mount Sinai School of Medicine, but now at Rockefeller University, and one from Yale University School of Medicine have agreed to continue their participation on this training grant. All candidates for this training program will be expected to devote a minimum of two years to training in either basic. The trainees will select a preceptor from one of the eight areas encompassed by this program: virology and gene therapy, immunology/transplant, genetics, developmental and stem cell biology, adhesion molecules and matrix, molecular basis of transport, vascular biology. Throughout the training period, trainees will devote approximately 90% of their time to research. The primary focus and vast majority of the trainee's time will be devoted to working on a specific, individualized research project under the guidance of one or more faculty preceptors. In addition, trainees will participate in weekly laboratory meetings, spend a portion of their time attending specific divisional, departmental and institutional research-oriented conferences, and will enroll in at least one didactic, graduate level course during the first and second years of training. MDs will not be assigned clinical duties during the period of their training